Using ambient light sensor to augment proximity sensor output

ABSTRACT

Apparatuses and methods to sense proximity of an object and operate a proximity sensor of a portable device. In some embodiments, a method includes receiving an ambient light sensor (ALS) output, and altering, based on the ALS output, an effect of a proximity sensor output on control of a proximity determination. The ALS sensor and the proximity sensor may be located adjacent to an earpiece of a portable device. In some cases, the proximity determination may be a proximity of an object to the proximity sensor, and altering the effect may include changing the proximity of the object from a proximity greater than a first threshold to a proximity less than the first threshold. Other apparatuses and methods and data processing systems and machine readable media are also described.

FIELD OF THE INVENTION

This invention relates to the field of portable devices and, inparticular, to systems and methods for detecting proximity of an object.

BACKGROUND OF THE INVENTION

Portable devices, such as cell phones, are becoming increasingly common.These portable devices have grown more complex over time, incorporatingmany features including, for example, MP3 player capabilities, webbrowsing capabilities, capabilities of personal digital assistants(PDAs) and the like.

The battery life of these portable devices, however, can be limited.Often, the primary draw of battery power is the display device for theseportable devices and, in particular, the backlight, which can be used toilluminate the display device. Thus, operation of these devices can behampered by not turning off the backlight when it is not needed, such aswhen the device is held next to or against to the users head. Similarly,these devices can be hampered by performing unintended functions as aresult of processing multiple unintentional inputs at an input devicethat contact a user's face or head.

Some of these portable devices may also include multiple sensors whichare used to detect the environment or context associated with theseportable devices. For example, U.S. patent application publication no.2005/0219228 describes a device which includes many sensors, including aproximity sensor and a light sensor. The outputs from the sensors areprocessed to determine a device environment or context. The light sensordetects ambient light levels and the proximity sensor detects aproximity to an object, such as a user's ear or face.

This is shown in FIG. 1, which shows a device 10. The device 10 includesa proximity sensor 12 mounted on a surface of the device 10 and anambient light sensor 14 also mounted on the surface of the device 10,such as near an earpiece or speaker. During operation, sensor 12 emitslight having known characteristics (e.g., frequency, wavelength, and/orwaveform) and detects the emitted light. A portion of the emitted lightfrom sensor 12 hits an object and is reflected by the object, when theobject is present above sensor 12. A portion of the reflected light isthen received or detected by sensor 12 to determine the proximity of theobject to sensor 12. However depending on the types, color, surfaceshape, and surface textures of materials of the object, the portion ofreflected light can vary widely causing large differences in proximitysensor proximity determinations for objects at the same distance fromsensor 12.

SUMMARY OF THE DESCRIPTION

The various apparatuses, software and methods described herein relate tosensing proximity of an object and operating a proximity sensor orportable device of an apparatus which receives a proximity sensor outputand an ambient light sensor output, and to systems, such as dataprocessing systems, which use software which (automatically or not)changes a proximity setting of a portable device according to theambient light sensor output.

According to some embodiments of the inventions, a method of sensingproximity includes receiving an ambient light sensor (ALS) output(level); and altering, (automatically or not) based on the ALS output,an effect of a proximity sensor output on control of a proximitydetermination. Also, the ALS output may be a visible light level ofambient light received by an ALS sensor adjacent to a proximity sensorthat provides the proximity sensor output, and the ALS sensor and theproximity sensor may be located adjacent to an earpiece of a portabledevice. In some cases, the proximity determination may be a proximity ofan object to the proximity sensor, and altering the effect may includechanging the proximity of the object from a proximity greater than afirst threshold to a proximity less than the first threshold. Moreover,the proximity sensor output may be a power level or a rate of change ofa power level of emitted IR light reflected by an object and received bythe proximity sensor. Similarly, the ALS output may be a power level ora rate of change of ambient light incident upon the sensor. Changes inthe ALS output may occur simultaneously with changes in the proximitysensor output. It is also considered that the ALS level may be a changein ALS level and cause the proximity determination to change. In someembodiments, a backlight of a display may be turned off and/orprocessing of inputs received at an input device may be disabled,(automatically or not), based on the proximity determination. Inaddition to the ALS output, according to embodiments, the effect of theproximity sensor output on the proximity determination may also bealtered, (automatically or not) based on a received accelerometer outputand/or a blob detect output.

According to some embodiments a method of operating a portable devicemay include receiving an ambient light sensor level; and (automaticallyor not) altering a proximity determination based on the ambient lightsensor level.

Finally, according to some embodiments, a method of operating a portabledevice may include receiving an ambient light sensor level; and(automatically or not) altering a proximity determination based on theambient light sensor level.

Other apparatuses, data processing systems, methods and machine readablemedia are also described.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and notlimitation in the figures of the accompanying drawings in which likereferences indicate similar elements.

FIG. 1 shows an example of a prior art device which includes twoseparate sensors;

FIG. 2 is a perspective view of a portable device in accordance with oneembodiment of the present invention;

FIG. 3 is a perspective view of a portable device in accordance with oneembodiment of the present invention;

FIG. 4 is a perspective view of a portable device in accordance with oneembodiment of the present invention;

FIG. 5A is a perspective view of a portable device in a firstconfiguration (e.g. in an open configuration) in accordance with oneembodiment of the present invention;

FIG. 5B is a perspective view of the portable device of FIG. 5A in asecond configuration (e.g. a closed configuration) in accordance withone embodiment of the present invention;

FIG. 6 is a block diagram of a system in which embodiments of thepresent invention can be implemented;

FIG. 7A is a schematic side view of a proximity sensor in accordancewith one embodiment of the present invention;

FIG. 7B is a schematic side view of an alternative proximity sensor inaccordance with one embodiment of the present invention;

FIG. 7C is a flow chart which shows a method of operating a proximitysensor which is capable of detecting light from a source other than theemitter of the proximity sensor;

FIG. 7D shows an example of a proximity sensor with associated logic;

FIG. 8 is a schematic side view of a combined proximity sensor andambient light sensor in accordance with one embodiment of the invention;

FIGS. 9A-C are views of user activities in accordance with embodimentsof the present invention;

FIG. 10A is a graph showing an example of a proximity sensor outputversus time;

FIG. 10B is a graph showing examples of a proximity sensor output and alight sensor output versus time;

FIG. 10C is a flow chart of a method that includes turning off abacklight, disabling processing of inputs, or taking another actionbased on proximity and light sensor outputs in accordance withembodiments of the present invention;

FIG. 10D is a flowchart of a method that includes altering an effect ofa proximity sensor output on a proximity determination based on aproximity sensor output and an ambient light sensor output;

FIG. 11 is a block diagram of a digital processing system in accordancewith one embodiment of the present invention.

DETAILED DESCRIPTION

Various embodiments and aspects of the inventions will be described withreference to details discussed below, and the accompanying drawings willillustrate the various embodiments. The following description anddrawings are illustrative of the invention and are not to be construedas limiting the invention. Numerous specific details are described toprovide a through understanding of various embodiments of the presentinvention. However, in certain instances, well-known or conventionaldetails are not described in order to provide a concise discussion ofembodiments of the present inventions.

Some portions of the detailed descriptions which follow are presented interms of algorithms which include operations on data stored within acomputer memory. An algorithm is generally a self-consistent sequence ofoperations leading to a desired result. The operations typically requireor involve physical manipulations of physical quantities. Usually,though not necessarily, these quantities take the form of electrical ormagnetic signals capable of being stored, processed, transferred,combined, compared, and otherwise manipulated. It has proven convenientat times, principally for reasons of common usage, to refer to thesesignals as bits, values, elements, symbols, characters, terms, numbers,or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the following discussion,it is appreciated that throughout the description, discussions utilizingterms such as “receiving” or “altering” or “processing” or “computing”or “calculating” or “determining” or “displaying” or the like, can referto the action and processes of a data processing device or system, orsimilar electronic device, that manipulates and transforms datarepresented as physical (electronic) quantities within the system'sregisters, storage devices, and memories into other data similarlyrepresented as physical quantities within the system's memories, storagedevices, or registers or other such information storage, transmission ordisplay devices.

The present invention can relate to an apparatus for performing one ormore of the acts or operations described herein. This apparatus may bespecially constructed for the required purposes, or it may comprise ageneral purpose computer selectively activated or reconfigured by acomputer program stored in the computer. Such a computer program may bestored in a machine (e.g. computer) readable storage medium, such as,but is not limited to, any type of disk including floppy disks, opticaldisks, CD-ROMs, and magnetic-optical disks, read-only memories (ROMs),random access memories (RAMs), flash memory, erasable programmable ROMs(EPROMs), electrically erasable programmable ROMs (EEPROMs), magnetic oroptical cards, or any type of media suitable for storing electronicinstructions, and each coupled to a bus.

A machine-readable medium includes any mechanism for storing ortransmitting information in a form readable by a machine (e.g., acomputer). For example, a machine-readable medium includes read onlymemory (“ROM”); random access memory (“RAM”); magnetic disk storagemedia; optical storage media; flash memory devices; electrical, optical,acoustical or other form of propagated signals (e.g., carrier waves,infrared signals, digital signals, etc.); etc.

At least certain embodiments of the present inventions include one ormore sensors to monitor user activity. At least certain embodiments ofthe present inventions also include a method and/or software to(automatically or not) change an effect of a proximity sensor output oncontrol of a proximity determination based on an ambient light sensor(ALS) output (level). The altered proximity determination may moreaccurately determine actual proximity, such as, for example, toautomatically activating or deactivating a backlight of a display deviceof the portable device or setting an input device of the portable deviceto a particular state, based on certain predetermined user activities.

At least certain embodiments of the inventions may be part of a digitalmedia player, such as a portable music and/or video media player, whichmay include a media processing system to present the media, a storagedevice to store the media and may further include a radio frequency (RF)transceiver (e.g., an RF transceiver for a cellular telephone) coupledwith an antenna system and the media processing system. In certainembodiments, media stored on a remote storage device may be transmittedto the media player through the RF transceiver. The media may be, forexample, one or more of music or other audio, still pictures, or motionpictures.

The portable media player may include a media selection device, such asa click wheel input device on an iPod® or iPod Nano® media player fromApple Computer, Inc. of Cupertino, Calif., a touch screen input device,pushbutton device, movable pointing input device or other input device.The media selection device may be used to select the media stored on thestorage device and/or the remote storage device. The portable mediaplayer may, in at least certain embodiments, include a display devicewhich is coupled to the media processing system to display titles orother indicators of media being selected through the input device andbeing presented, either through a speaker or earphone(s), or on thedisplay device, or on both display device and a speaker or earphone(s).Examples of a portable media player are described in published U.S.patent application numbers 2003/0095096 and 2004/0224638, both of whichare incorporated herein by reference.

Embodiments of the inventions described herein may be part of othertypes of data processing systems, such as, for example, entertainmentsystems or personal digital assistants (PDAs), or general purposecomputer systems, or special purpose computer systems, or an embeddeddevice within another device, or cellular telephones which do notinclude media players, or devices which combine aspects or functions ofthese devices (e.g., a media player, such as an iPod®, combined with aPDA, an entertainment system, and a cellular telephone in one portabledevice).

FIG. 2 illustrates a portable device 30 according to one embodiment ofthe invention. FIG. 2 shows a wireless device in a telephoneconfiguration having a “candy-bar” style. In FIG. 2, the wireless device30 may include various features such as a housing 32, a display device34, an input device 36 which may be an alphanumeric keypad, a speaker38, a microphone 40 and an antenna 42. The wireless device 30 also mayinclude an ambient light sensor (ALS) and/or proximity sensor 44 and anaccelerometer 46. It will be appreciated that the embodiment of FIG. 2may use more or fewer sensors and may have a different form factor fromthe form factor shown in FIG. 2.

The speaker 38 is also shown at an upper portion of the housing 32 abovethe display device 34. The microphone 40 is shown at a lower portion ofthe housing 32, below the input device 36. It will be appreciated thatthe speaker 38 and microphone 40 can be positioned at any location onthe housing, but are typically positioned in accordance with a user'sear and mouth, respectively. The proximity sensor 44 is shown at or nearthe speaker 38 and at least partially within the housing 32. Sensor 44may be located “adjacent” to speaker 38 (e.g., an earpiece). The term“earpiece” may describe a speaker, an audio transducer, and/or anotherdevice for producing sound to be heard by a user's ear. Also, in someembodiments, the term “adjacent” may describe a location of onecomponent on a surface, housing, or portion of a device that is at, on,or within 0.1, 0.25, 0.5, 1, 2, 4, 8, 10 or any combination thereof ofinches of another component (e.g., from the closest edges of onecomponent, like a sensor, and another component, like an earpiece).Proximate may also describe one component touching, at, on, proximateto, adjacent to, next to, and/or in the same location as anothercomponent. Also, in some embodiments, the term “adjacent” may describe alocation that is in a range of between 0.1 millimeters (mm) and 2,000 mmfrom another location. Moreover, in some embodiments, the term“adjacent” may describe a location that is in a range of between 0.01 mmand 200 mm from another location. Likewise, in some embodiments, theterm “adjacent” may describe a location that is in a range of betweentouching and 30 mm from another location. The accelerometer 46 is shownat a lower portion of the housing 32 and within the housing 32. It willbe appreciated that the particular locations of the above-describedfeatures may vary in alternative embodiments. It will also beappreciated that the types of sensors, number of sensors, and particularlocations of the above-described sensors and features may vary inalternative embodiments.

The display device 34 may be, for example, a liquid crystal display(LCD) (e.g., with a backlight) which does not include the ability toaccept inputs or a touch input screen which also includes an LCD. Sensor44 may be operated as described herein and may detect proximity asdescribed herein. The input device 36 may include, for example, buttons,switches, dials, sliders, keys or keypad, navigation pad, touch pad,touch screen, and the like.

Any well-known speaker, microphone and antenna can be used for speaker38, microphone 40 and antenna 42, respectively.

The ALS and/or proximity sensor 44 may describe one or more ALS sensors,proximity sensors, and/or combined proximity and ALS sensors. Sensor 44may detect location (e.g. at least one of X, Y, Z), direction of motion,speed, etc. of objects relative to the wireless device 30 (e.g., tosensor 44), and/or an ambient light environment at device 30 (e.g., atsensor 44). A location or proximity determination of an object relativeto the wireless device can be represented as a distance between theclosest point or surface of the object and the proximity sensor of thedevice, in at least certain embodiments. The proximity sensor maygenerate location or movement output data or both, which may be used todetermine the proximity of objects relative to the portable device 30and/or relative to proximity sensor 44. An example of a proximity sensoris shown in FIG. 7A.

In addition, a processing device (not shown) is coupled to the proximitysensor(s) 44. The processing device may be used to determine thelocation of objects and/or an ambient light environment relative to theportable device 30, the ALS and/or or proximity sensor 44 based on theambient light, location and/or movement data provided by the ALS and/orproximity sensor 44. The ALS and/or proximity sensor may continuously orperiodically monitor the ambient light and/or object location. Theproximity sensor may also be able to determine the type of object it isdetecting. The ALSs described herein may be able to detect in intensity,brightness, amplitude, or level of ambient light and/or ambient visiblelight, incident upon the ALS and/or proximity sensor.

Additional information about proximity sensors can be found inco-pending U.S. patent application Ser. No. 11/241,839, titled“PROXIMITY DETECTOR IN HANDHELD DEVICE,” and U.S. patent applicationSer. No. 11/240,788, titled “PROXIMITY DETECTOR IN HANDHELD DEVICE;”U.S. patent application Ser. No. 11/165,958, titled “METHODS ANDAPPARATUS FOR REMOTELY DETECTING PRESENCE,” filed Jun. 23, 2005; andU.S. Pat. No. 6,583,676, titled “PROXIMITY/TOUCH DETECTOR ANDCALIBRATION CIRCUIT,” issued Jun. 24, 2003, all of which areincorporated herein by reference in their entirety.

According to one embodiment, the accelerometer 46 is able to detect amovement including an acceleration or de-acceleration of the wirelessdevice. The accelerometer 46 may generate movement output data formultiple dimensions, which may be used to determine a direction ofmovement of the wireless device. For example, the accelerometer 46 maygenerate X, Y and Z axis acceleration information when the accelerometer46 detects that the portable device is moved. In one embodiment, theaccelerometer 46 may be implemented as described in U.S. Pat. No.6,520,013, which is incorporated herein by reference in its entirety.Alternatively, the accelerometer 46 may be a KGF01 accelerometer fromKionix or an ADXL311 accelerometer from Analog Devices or otheraccelerometers which are known in the art.

In addition, a processing device (not shown) is coupled to theaccelerometer(s) 46. The processing device may be used to calculate adirection of movement, also referred to as a movement vector of thewireless device 30. The movement vector may be determined according toone or more predetermined formulas based on the movement output data(e.g., movement in X, Y and Z) provided by accelerometer 46. Theprocessing device may be integrated with the accelerometer 46 orintegrated with other components, such as, for example, a chipset of amicroprocessor, of the portable device.

The accelerometer 46 may continuously or periodically monitor themovement of the portable device. As a result, an orientation of theportable device prior to the movement and after the movement may bedetermined based on the movement output data provided by theaccelerometer attached to the portable device. Additional informationabout accelerometers can be found in co-pending U.S. patent applicationSer. No. 10/986,730, filed Nov. 12, 2004, which is hereby incorporatedherein by reference in its entirety.

The output data acquired from the ALS and/or proximity sensor 44 and theaccelerometer 46 can be combined together, or used alone, to gatherinformation about the user's activities. The output data from the ALSand/or proximity sensor 44, the accelerometer 46 or both can be used,for example, to activate/deactivate a display backlight, initiatecommands, make selections, control scrolling or other movement in adisplay, control input device settings, or to make other changes to oneor more settings of the device.

FIG. 3 shows an alternative portable device 30 a, which is similar tothe portable device 30 illustrated in FIG. 2. The portable device 30 ashown in FIG. 3 can differ from the portable device 30 shown in FIG. 2in that the ALS and/or proximity sensor 44 a (FIG. 3) is located at ornear the microphone 40.

FIG. 4 shows a portable device 50 in accordance with one embodiment ofthe invention. The portable device 50 may include a housing 52, adisplay/input device 54, a speaker 56, a microphone 58 and an optionalantenna 60 (which may be visible on the exterior of the housing or maybe concealed within the housing). The portable device 50 also mayinclude an ALS and/or proximity sensor 62, other sensors, and anaccelerometer 64. The portable device 50 may be a cellular telephone ora device which is an integrated PDA and a cellular telephone or a devicewhich is an integrated media player and a cellular telephone or a devicewhich is both an entertainment system (e.g. for playing games) and acellular telephone, or the portable device 50 may be other types ofdevices described herein. In one particular embodiment, the portabledevice 50 may include a cellular telephone and a media player and a PDA,all contained within the housing 52. The portable device 50 may have aform factor which is small enough that it fits within the hand of anormal adult and is light enough that it can be carried in one hand byan adult. It will be appreciated that the term “portable” means thedevice can be easily held in an adult user's hands (one or both); forexample, a laptop computer and an iPod are portable devices.

In one embodiment, the display/input device 54 may include a multi-pointtouch input screen (e.g., user input device) in addition to being adisplay, such as an LCD. For instance, in at least certain embodiments,the device may have at least one input device (e.g. a keypad or keyboardor touch input panel) which is designed to receive intentional userinputs (e.g. which specify a specific user entry) in addition to one ormore sensors which are distinct and separate from the at least one inputdevice and which sensors are not designed to receive intentional userinputs. In fact, a user may not even be aware of the presence of the oneor more sensors on the device.

In one embodiment, the multi-point touch screen is a capacitive sensingmedium configured to detect one or more touches. For instance, the inputdevice may provide a “blob” detection output, a “far-field recognition”output, and/or an “irregular contacts” output in response or based onreceiving a number of simultaneous capacitive input detections to anumber of input keys or locations of an input device (e.g., such asinputs that form an irregular location pattern or shape). Also, the blobdetected may be multiple touches (e.g., blobs on the display from auser's face or multiple fingers concurrently touching or nearly touchingthe display) or near touches (e.g., blobs on the display) that occur atthe same time (e.g., simultaneously) and at distinct locations in theplane of the touch panel and to produce distinct signals representativeof the location of the touches on the plane of the touch panel for eachof the multiple touches. Additional information about multi-point inputtouch screens can be found in co-pending U.S. patent application Ser.No. 10/840,862, filed May 6, 2004 (see published U.S. patent application20060097991), which is incorporated herein by reference in its entirety.A multi-point input touch screen may also be referred to as amulti-touch input panel. Additional information about a “blob” detectionoutput, a “far-field recognition” output, and/or an “irregular contacts”output is provided further below.

A processing device (not shown) may be coupled to the display/inputdevice 54. The processing device may be used to calculate proximity, ALSand/or touches on the touch panel. The display/input device 54 can usethe detected touch (e.g., blob or blobs from a user's face) output datato, for example, determine the proximity or location of certain objectsand to also identify the type of object touching (or nearly touching)the display/input device 54.

The output data acquired from the ALS and/or proximity sensor 62 and thedisplay/input device 54 can be combined to gather information about theuser's activities as described herein. The output data from the ALSand/or proximity sensor 62 and the display/input device 54 can be usedto change one or more settings of the portable device 50, such as, forexample, change an illumination or backlight setting of thedisplay/input device 54.

In embodiments, the display/input device 54 occupies a large portion,substantially all of, or at least 75% of one surface (e.g. the topsurface) of the housing 52 of the portable device 50. In an alternateembodiment the display/input device can occupies less than 75% of onesurface (e.g. the top surface) of the housing 52 of the portable device50. Also, in alternative embodiments, the portable device 50 may includea display which does not have input capabilities, but the display stilloccupies a large portion of one surface of the portable device 50. Inthis case, the portable device 50 may include other types of inputdevices such as a QWERTY keyboard or other types of keyboard which slideout or swing out from a portion of the portable device 50.

FIGS. 5A and 5B illustrate a portable device 70 according to oneembodiment of the invention. The portable device 70 may be a cellulartelephone which includes a hinge 87 that couples a display housing 89 toa keypad housing 91. The hinge 87 allows a user to open and close thecellular telephone so that it can be placed in at least one of twodifferent configurations shown in FIGS. 5A and 5B. In one particularembodiment, the hinge 87 may rotatably couple the display housing to thekeypad housing. In particular, a user can open the cellular telephone toplace it in the open configuration shown in FIG. 5A and can close thecellular telephone to place it in the closed configuration shown in FIG.5B. The keypad housing 91 may include a keypad 95 which receives inputs(e.g. telephone number inputs or other alphanumeric inputs) from a userand a microphone 97 which receives voice input from the user. Thedisplay housing 89 may include, on its interior surface, a display 93(e.g. an LCD) and a speaker 98 and an ALS and/or proximity sensor 84adjacent to speaker 98; on its exterior surface, the display housing 89may include a speaker 96, a temperature sensor 94, a display 88 (e.g.another LCD), an ambient light sensor 92, and an ALS and/or proximitysensor 84A adjacent to speaker 96. Hence, in this embodiment, thedisplay housing 89 may include a first ALS and/or proximity sensor onits interior surface and a second ALS and/or proximity sensor on itsexterior surface. The first ALS and/or proximity sensor may be used todetect an ambient light environment and/or a user's head or ear beingwithin a certain distance of the first ALS and/or proximity sensor andto cause an illumination setting of displays 93 and 88 to be changed(automatically or not) in response to this detecting.

In at least certain embodiments, the portable device 70 may containcomponents which provide one or more of the functions of a wirelesscommunication device such as a cellular telephone, a media player, anentertainment system, a PDA, or other types of devices described herein.In one implementation of an embodiment, the portable device 70 may be acellular telephone integrated with a media player which plays MP3 files,such as MP3 music files.

It is also considered that and electronic device or portable devicedescribed herein, such as the devices shown in FIGS. 2, 3, 4, 5A and 5B,may have a form factor or configuration having a “candy-bar” style, a“flip-phone” style, a “sliding” form, and or a “swinging” form. Forexample, a “candy-bar” style may be described above in FIG. 2 forwireless device 30. Also, a “flip-phone” style may be described above inFIG. 5A and 5B for device 70. A “sliding” form may describe where akeypad portion of a device slides away from another portion (e.g., theother portion including a display) of the device, such as by slidingalong guides or rails on one of the portions. A “swinging” form maydescribe where a keypad portion of a device swings sideways away (asopposed to the “flip-phone” style swinging up and down) from anotherportion (e.g., the other portion including a display) of the device,such as by swinging on a hinge attaching the portions.

Each of the devices shown in FIGS. 2, 3, 4, 5A and 5B may be a wirelesscommunication device, such as a cellular telephone, and may include aplurality of components which provide a capability for wirelesscommunication. FIG. 6 shows an embodiment of a wireless device 100 whichincludes the capability for wireless communication. The wireless device100 may be included in any one of the devices shown in FIGS. 2, 3, 4, 5Aand 5B, although alternative embodiments of those devices of FIGS. 2-5Bmay include more or fewer components than the wireless device 100.

Wireless device 100 may include an antenna system 101. Wireless device100 may also include one or more digital and/or analog radio frequency(RF) transceivers 102, coupled to the antenna system 101, to transmitand/or receive voice, digital data and/or media signals through antennasystem 101. Transceivers 102, may include on or more infrared (IR)transceivers, WiFi transceivers, Blue Tooth™ transceivers, and/orwireless cellular transceivers.

Wireless device 100 may also include a digital processing device orsystem 103 to control the digital RF transceivers and to manage thevoice, digital data and/or media signals. Digital processing system 103may be a general purpose processing device, such as a microprocessor orcontroller for example. Digital processing system 103 may also be aspecial purpose processing device, such as an ASIC (application specificintegrated circuit), FPGA (field-programmable gate array) or DSP(digital signal processor). Digital processing system 103 may alsoinclude other devices, as are known in the art, to interface with othercomponents of wireless device 100. For example, digital processingsystem 103 may include analog-to-digital and digital-to-analogconverters to interface with other components of wireless device 100.Digital processing system 103 may include a media processing system 109,which may also include a general purpose or special purpose processingdevice to manage media, such as files of audio data.

Wireless device 100 may also include a storage device 104 (e.g.,memory), coupled to the digital processing system, to store data and/oroperating programs for the wireless device 100. Storage device 104 maybe, for example, any type of solid-state or magnetic memory device.

Wireless device 100 may also include one or more input devices 105(e.g., user interface controls, or I/O devices), coupled to the digitalprocessing system 103, to accept user inputs (e.g., telephone numbers,names, addresses, media selections, user settings, etc.) Input device105 may be, for example, one or more of a keypad, a touchpad, a touchscreen, a pointing device in combination with a display device orsimilar input device.

Wireless device 100 may also include at least one display device 106,coupled to the digital processing system 103, to display text, images,and/or video. Device 106 may display information such as messages,telephone call information, user settings, user selected brightnesslevels, contact information, pictures, movies and/or titles or otherindicators of media being selected via the input device 105. Displaydevice 106 may be, for example, an LCD display device. In oneembodiment, display device 106 and input device 105 may be integratedtogether in the same device (e.g., a touch screen LCD such as amulti-touch input panel which is integrated with a display device, suchas an LCD display device). Examples of a touch input panel and a displayintegrated together are shown in U.S. published application No.20060097991. The display device 106 may include a backlight 106 a toilluminate the display device 106 under certain circumstances. It willbe appreciated that the wireless device 100 may include multipledisplays.

Wireless device 100 may also include a battery 107 to supply operatingpower to components of the system including digital RF transceivers 102,digital processing system 103, storage device 104, input device 105,microphone 105A, audio transducer 108 (e.g., a speaker or earpiece),media processing system 109, sensor(s) 110, and display device 106.Battery 107 may be, for example, a rechargeable or non-rechargeablelithium or nickel metal hydride battery.

Wireless device 100 may also include one or more sensors 110 coupled tothe digital processing system 103. The sensor(s) 110 may include, forexample, one or more of a proximity sensor, accelerometer, touch inputpanel, ambient light sensor, ambient noise sensor, temperature sensor,gyroscope, a blob sensor, an irregular contacts sensor, a capacitivesensor, a far-field recognition sensor, a hinge detector, a positiondetermination device, an orientation determination device, a motionsensor, a sound sensor, a radio frequency electromagnetic wave sensor,and other types of sensors and combinations thereof.

Also, in some embodiments, sensors, displays, transceivers, digitalprocessing systems, processor, processing logic, memories and/or storagedevice may include one or more integrated circuits disposed on one ormore printed circuit boards (PCB).

FIGS. 7A and 7B illustrate exemplary proximity sensors in accordancewith embodiments of the invention. It will be appreciated that, inalternative embodiments, other types of proximity sensors, such ascapacitive sensors or sonar-like sensors, may be used rather than theproximity sensors shown in FIGS. 7A and 7B. In FIG. 7A, the proximitysensor 120 includes an emitter 122, a detector 124, and a window 126.The emitter 122 generates light in the infrared (IR) bands, and may be,for example, a Light Emitting Diode (LED). The detector 124 isconfigured to detect changes in light intensity and may be, for example,a phototransistor. The window 126 may be formed from translucent orsemi-translucent material. In one embodiment, the window 126 is anacoustic mesh, such as, for example, a mesh typically found with amicrophone or speaker of the portable device. In other embodiments, thewindow 126 may be MicroPerf, IR transparent strands wound in a mesh, ora cold mirror.

During operation, the light from the emitter 122 hits an object 128 andscatters (e.g., is reflected by the object) when the object is presentabove the window 126. The light from the emitter may be emitted insquare wave pulses which have a known frequency, thereby allowing thedetector 124 to distinguish between ambient light and light from emitter122 which is reflected by an object (e.g., a shape and/or material ofthe object), such as the user's head, hair, or ear or a materialthereof, back to the detector 124. At least a portion of the scatteredlight is reflected towards the detector 124. The reflected light power(e.g., intensity) and/or increase in power is detected by the detector124, and output as an output signal to a device (e.g., a processor,processing system, or software). This output signal is interpreted bythe device (not shown in FIG. 7A) to make a proximity determination thatan object is present within a short distance of the detector 124. If noobject is present or the object is beyond a certain distance from thedetector 124, an insufficient or smaller amount of the emitted light isreflected back towards the detector 124, and the output signal isinterpreted by the device to mean that an object is not present or is ata relatively large distance. In each case, the proximity sensor ismeasuring (e.g., outputting) the intensity of reflected light which isrelated to the distance between the object which reflects the light anddetector 124.

In FIG. 7B, the emitter 122 and detector 124 of the proximity sensor areangled inward towards one another to improve detection of the reflectedlight, but the proximity sensor of FIG. 7B otherwise operates in amanner similar to the proximity sensor of FIG. 7A.

A proximity sensor in one embodiment of the inventions includes theability to both sense proximity and detect electromagnetic radiation,such as ambient light, from a source other than the emitter of theproximity sensor. The use of IR light for both the emitter and thedetector of the proximity sensor may be advantageous because IR light issubstantially present in most sources of ambient light (such assunshine, incandescent lamps, LED light sources, candles, and to someextent, even fluorescent lamps). Thus, the detector can detect ambientIR light, which will generally represent, in most environments, ambientlight levels at wavelengths other than IR, and use the ambient IR lightlevel to effectively and reasonably accurately represent ambient lightlevels at wavelengths other than IR.

A method of operating a proximity sensor which includes the ability toboth sense proximity and detect light is shown in FIG. 7C and anexample, in block diagram form, of such a proximity sensor is shown inFIG. 7D. The method of FIG. 7C may use the proximity sensor shown inFIG. 7D or other proximity sensors. The method includes operation 135 inwhich electromagnetic radiation (e.g. IR light) is emitted from theemitter of the proximity sensor. The emitter may emit the radiation in aknown, predetermined pattern (e.g. a train of square wave pulses ofknown, predetermined pulse width and frequency) which allows a detectorto distinguish between ambient radiation and radiation from the emitter.In operation 137, the detector of the proximity sensor detects andmeasures light from the emitter when the detector is operating inproximity sensing mode. A processor coupled to the detector may processthe output signal from the detector to identify the known predeterminedpattern of radiation from the emitter and to measure the amount ofradiation from the emitter. In operation 139, the detector is used in amode to sense radiation (e.g. ambient IR light) from a source other thanthe emitter; this operation may be implemented in a variety of ways. Forexample, the emitted light from the emitter may be disabled by a shutter(either a mechanical or electrical shutter) placed over the emitter orthe emitter's power source may be turned off (thereby stopping theemission of radiation from the emitter). Alternatively, known signalprocessing techniques may be used to remove the effect of the emitter'semitted light which is received at the detector in order to extract outthe light from sources other than the emitter. It will be appreciatedthat operations 135, 137 and 139 may be performed in a sequence which isdifferent than the sequence shown in FIG. 7C.

FIG. 7D shows an embodiment of a range sensing IR proximity sensor 145which includes the ability to sense and detect proximity and to detectand measure ambient light levels (e.g., sent as proximity sensor and/orALS outputs). The proximity sensor 145 includes an IR emitter 147 (e.g.an IR LED) and an IR detector 149. An optional shutter (e.g. an LCDelectronic shutter) may be disposed over the emitter 147. The IR emitter147 and the IR detector 149 may be coupled to a microcontroller 151which may control switching between proximity sensing mode and ambientlight sensing mode by either closing and opening an optional shutter orby turning on and off the power to the IR emitter 147. The output fromthe IR detector 149 may be provided from the microcontroller 151 to themicroprocessor 153 which determines, from output data from the proximitysensor 145, at least one proximity output value and determines at leastone ambient light level output value. In an alternative embodiment, themicroprocessor may be coupled to the IR emitter 147 and to the IRdetector 149 without an intervening microcontroller, and themicroprocessor may perform the functions of the microcontroller (e.g.the microprocessor may control switching between proximity sensing modeand ambient light sensing mode). The microprocessor 153 may be coupledto other components 155, such as input (e.g. keypad) or output (e.g.display) devices or memory devices or other sensors or a wirelesstransceiver system, etc., such as to alter settings of the device. Forexample, the microprocessor 153 may be the main processor of thewireless device 100 shown in FIG. 6. In those embodiments in which ashutter over the IR emitter is not used and IR emissions from the IRemitter 147 are received at the IR detector 149 while the IR detector149 is measuring ambient light levels, the microprocessor 153 (or themicrocontroller 151) may filter out the known predetermined pattern ofIR light from the IR emitter 147 in order to extract a signal from theIR detector 149 representing the IR light level from sources other thanthe IR emitter 147. Additional information about such sensors can befound in co-pending U.S. patent application Ser. No. 11/600,344, filedNov. 15, 2006 titled “INTEGRATED PROXIMITY SENSOR AND LIGHT SENSOR”which is incorporated herein by reference in its entirety.

FIG. 8 is a schematic side view of a combined proximity sensor andambient light sensor in accordance with one embodiment of the invention.FIG. 8 shows combined sensor 820 including emitter 822, detector 824 andcovering 826, such as to detect the proximity of an object to the sensorand an ambient light level or intensity at the sensor. FIG. 8 also showslogic 830, such as a processor and/or processing logic for controlling,receiving, scaling, subtracting, and/or determining outputs ofcomponents of sensor 820 (e.g., emitter 822, detector 824, logic 830 andcomponents thereof) to determine proximity and/or ambient light. FIG. 8also shows fence 810, such as a fence that is antireflective ornon-transmissive for radiation of emitter 822. Fence 810 may be a fence,a wall or a barrier disposed between the emitter and the detector,extending all the way up to covering 826. Fence 810 is optional.Covering 826 may or may not be a covering similar to covering 126,emitter 822 may or may not be an emitter similar to emitter 122 asdescribed above for FIGS. 7A through 7D.

Emitter 822 is shown emitting emitted radiation 870 which may berefracted as refracted radiation 872 by covering 826. Emitter 822 may bean infrared (IR) light emitter or transmitter, and may emit IR lightmodulated at a modulation frequency (e.g., as predetermined pattern orpulses as described for FIGS. 7C and 7D). Also, radiation 870 may bereflected by object 888 as shown by reflected emitter radiation 874,which may be received by detector 824. Object 888 may be an objecthaving proximity D and an IR light reflective surface or material, andmay be an object like object 128.

FIG. 8 shows detector 824 including sensor 850, sensor 852, and filter856. Sensor 850 may be described as a sensor configured to detectelectromagnetic radiation from emitter 822, and ambient radiation 872.Sensor 852 may be a sensor as described above for sensor 850, exceptthat sensor 852 is covered with or has filter 856 disposed betweensensor 852 and radiation 870, 874, and 872. Filter 856 may be describedas a passband filter for IR light, but not passing visible light, suchas to pass IR light from incandescent bulbs and fluorescent bulb, aswell as radiation 870 and 874, but not to pass visible light fromincandescent bulbs and fluorescent bulb. Thus, sensor 852 may detectelectromagnetic radiation from radiation 870, radiation 874, and/orambient IR radiation from radiation 872, but may not receive or sensevisible light from radiation 872.

Logic 830 may modulate the emitter IR light and/or to turn the emitteron and off. The IR light from radiation 872 may be filtered out ordistinguished from the output of sensor 852 by logic 830. Distinguishingthe emitted IR from ambient IR by detecting for emitted IR during onetime period and for ambient IR during another (e.g., as predeterminedpattern or pulses as described for FIGS. 7C and 7D) may be described asTDM, timeslicing and multiplexing, and/or using a waveform filter.Detector 824 and/or logic 830 may be used to sense proximity (e.g., sentas proximity sensor and/or ALS outputs) of the object to combined sensor820, and may determine a visible light intensity of ambient radiation872. Additional information about such combined or integrated sensorscan be found in U.S. patent application Ser. No. 11/650,117, filed Jan.5, 2007 by ANTHONY M. FADELL AND ACHIM PANTFOERDER, titled “INTEGRATEDPROXIMITY SENSOR AND LIGHT SENSOR” which is incorporated herein byreference in its entirety.

The term “substantially” may refer to the specific value noted herein,or, in some cases, a range within 1, 2 or 5 percent of that value. Theterms “processing logic” as described herein may describe a device, aprocessor, circuitry, software, a memory, and/or a combination of any orall of the above. Similarly, the term “sensor” may include the abovedescriptions for processing logic. Also, use of the term “detect” andderivations therefrom may be similar to that described herein for use ofthe term “sense” and derivations thereof, and vice versa.

It will be appreciated that at least some of the sensors which are usedwith embodiments of the inventions may determine or provide output datawhich represents an analog value. In other words, the data represents avalue which can be any one of a set of possible values which can varycontinuously or substantially continuously, rather than being discretevalues which have quantum, discrete jumps from one value to the nextvalue. Further, the value represented by the data may not bepredetermined. For example, in the case of a distance measured by aproximity sensor, the distance is not predetermined, unlike values ofkeys on a keypad which represent a predetermined value. For example, aproximity sensor may determine or provide output data (e.g., via anoutput a signal) that represents a distance which can vary continuouslyor nearly continuously in an analog fashion. In the case of such aproximity sensor, the output may be based on or proportional to theintensity of reflected light which originated from the emitter of theproximity sensor. A temperature sensor may determine or provide outputdata that represents a temperature, which is an analog value. A lightsensor, such as an ambient light sensor, may determine or provide outputdata that represents a light intensity which is an analog value. Amotion sensor, such as an accelerometer, may determine or provide outputdata which represents a measurement of motion (e.g. velocity oracceleration or both). A gyroscope may determine or provide output datawhich represents a measurement of orientation (e.g. amount of pitch oryaw or roll). A sound sensor may determine or provide output data whichrepresents a measurement of sound intensity. For other types of sensors,the output data determined or provided by the sensor may represent ananalog value.

Any or all of the sensors mentioned herein may send output data orsignals which when received (e.g., by a digital processing system, adata processing device, an electronic device or “device”, a processor oran executing software application) are included in or are a basis forsensing proximity, operating a proximity sensor and/or operating aportable device as described herein, such as to (automatically in somecases) set or alter a proximity determination. The proximitydeterminations may provide evidenced of, determine, or identify useractivities. In some cases, a proximity “determination” describes alocation, distance, direction or proximity of an object to the device,earpiece, and/or proximity sensor. For instance, the output of sensors(e.g., an accelerometer output greater than a threshold) and a proximitydetermination (e.g., of an object, such as a large object, in very closeproximity) may be used to determine that the device is held at oradjacent to the user's head or ear, which causes the device to turn offa display or backlight to save energy. The determination may consider orbe based on output, such as a power level (e.g., value) or rate ofchange of power level of an output signal of a proximity sensor and anALS. The output signal may be described as a signal power level,intensity, amplitude, reading, or value output by a sensor based on,proportional to, or otherwise derived from a power or intensity of lightreceived, detected or sensed by the sensor. For a proximity sensor thelight received may be received IR light emitted by the sensor andreflected by an object (e.g., a reflection of an emitted IR signal,incident upon the proximity sensor). For an ALS, the light received maybe ambient light incident upon the sensor.

Moreover, based on the proximity determination various device settingsor actions may be altered, made or performed (e.g., automatically or notby a digital processing system, device, processor or executing softwareapplication) such as, for example, activating, deactivating, changing,controlling, and/or altering a setting and/or parameter of a backlight(e.g., backlight 106 a). Other responses that may be performed includechanging a setting of, or disabling processing of inputs received at aninput device (e.g., input device 105). Also, the descriptions forsensors 110, 120, 145, 820, and the like apply to other sensor describedherein, including those referred to for FIGS. 1-11.

FIGS. 9A-C illustrate exemplary user activities that can be determinedbased on output signals or data received from one or more sensors of theportable device. Exemplary user activities include, but are not limitedto, the user looking directly at the portable device (FIG. 9A), such aswhere the device has a proximity, location, or proximity determinationbetween the device (e.g., an earpiece or sensor of the device) and theuser's head 988 (e.g., an object which may describe or be described byobject 128 or 888) of long distance proximity PL. Other examples ofproximity PL may include when the device is set down or placed on asurface (not shown). Also, in some embodiments, a long distanceproximity PL may describe a location that is in a range of between 0.1millimeters (mm) and 20,000 mm from another location. Other distancesare also considered for proximity PL, such as greater than 6, 12, or 18inches between two locations.

Other user activities include the user holding the portable device at ornear their ear (FIG. 9B), such as where the device has a proximity,location, or proximity determination of very close distance or touchingproximity P1. Other examples of proximity P1 may include the devicebeing in a user's pocket or a case (not shown). Moreover, in someembodiments, a very close distance or touching proximity P1 may describea location that is in a range of between touching and 200 mm fromanother location. Other distances are also considered for proximity P1,such as less than 0.01, 0.1, 1, 2, or 3 inches between two locations.

More user activities include the user holding the device at, or movingthe portable device between a long and a very close distance proximity(FIG. 9C), such as where the device has a proximity, location, orproximity determination of a middle distance proximity P2. Also, in someembodiments, a middle distance proximity P2 may describe a location thatis in a range of between 0.01 mm and 2,000 mm from another location.Other distances are also considered for proximity P2, such as ranges ofbetween 0.01 and 0.1 inches, 0.1 and 1 inch, 0.1 and 6 inches, 1 and 2inches, 1 and 6 inches, or 2 and 20 inches between two locations.

Additional information about user activities and/or gestures that can bemonitored in accordance with embodiments of the present invention aredisclosed in U.S. patent application Ser. No. 10/903,964, titled“GESTURES FOR TOUCH SENSITIVE INPUT DEVICES,” filed Jul. 30, 2004, U.S.patent application Ser. No. 11/038,590, titled “MODE-BASED GRAPHICALUSER INTERFACES FOR TOUCH SENSITIVE INPUT DEVICES,” filed Jan. 18, 2005,all of which are incorporated herein by reference in their entirety.

However as noted, depending on the types, colors, surface shapes, andsurface textures of materials of the object, the amount of emitted lightreflected (e.g., “IR light reflectiveness”) can vary widely causinglarge differences in proximity determinations for objects at the samedistance from the proximity sensor. For example, material types such asglass, plastic, metal, and skin are more IR light reflective as comparedto cloth, and hair (e.g., which are more IR light absorptive). Also,material colors such as white, silver, and gold are more IR lightreflective as compared to black, green, and grey. Next, material surfaceshapes such as surfaces having most or a portion of the surfaceperpendicular to the IR emitter or sensor of a proximity sensor are moreIR light reflective as compared to shapes having most or all of theirsurfaces at angles (e.g., at 45 degree, or 90 degree angles) withrespect to the emitter or sensor. Finally, material surface texturessuch as large smooth, curved or flat surfaces are more IR lightreflective as compared to bubbled, porous, angled, tall or small featuretextured surfaces. More particularly, dark or grey hair is less IR lightreflective than skin or a balder head. Thus, a user holding the portabledevice at or near their ear (FIG. 9B) may result in a middle distanceproximity P2 output signal received from proximity sensor adjacent tothe earpiece (e.g., a signal higher than normal or higher than longdistance proximity PL), when the actual proximity determination shouldbe for a very close distance or touching proximity proximity P1 (e.g., astrikingly high sensor output received for a balder head, shinierobject, or more highly IR light reflective object).

Also, as noted above, the display (e.g., a liquid crystal display (LCD))and/or backlight of the display device may represent one of the largestbattery draws or drains of a portable device. In these cases, the longerduration or more time the backlight is on, the more battery energy isconsumed by the backlight. Thus, in some embodiments, it may bebeneficial to turn off, power down, and/or reduce the amount of time thebacklight is on to reduce the effect or amount of battery draw or drainthat the backlight of the display device has on the battery.

According to some embodiments, to more accurately determine “actualproximity”, an ALS output power level or change in power level receivedfrom one or more sensors may be used, consulted, or a basis to operate aproximity sensor of a portable device by (automatically in some cases)setting, altering or changing a proximity determination. A proximitydetermination may identify or determine a distance, location or “actualproximity” between an object's surface (e.g., reflecting IR lightemitted by an emitter) and a sensor, earpiece or device. The proximitydetected may be different than a proximity according to a sensor outputsignal. In other words, the sensor output signal may or may not identifyor determine the “actual proximity” or distance between the surface ofthe object and the sensor, such as depending on the types, colors,surface shapes, and/or surface textures of materials of the object(e.g., with respect to IR light reflectiveness). Thus, the proximitydetermination may be altered based on the output signal of an ALS tomore accurately tell if the user is looking directly at the portabledevice (FIG. 9A proximity PL), holding the portable device at or neartheir ear (FIG. 9B proximity P1), or moving the portable device betweena long and a very close distance proximity (FIG. 9C proximity P2).

The more accurate proximity and/or user action may be used turn on, turnoff, set, change, or alter device settings. Such device settingsinclude, turning on/off a display or a processor processing inputs of aninput device. The setting or changing may be to power up, turn on, powerdown, or turn off, a setting device or parameter of the device suchaccording to an output level or change in level of an ALS output and aproximity sensor output. In some cases, when a change to a light sensoroutput (e.g., a change in ambient light level) goes below or is lessthan a threshold limit and a proximity sensor output goes above or isgreater than a threshold limit, then a setting of the device powersdown, or turns off. This situation may describe where the device is heldat a very close distance or touching proximity P1 range to a lower IRreflective object (e.g., user's dark or grey color hair). Thus, althoughthe proximity determination according to the proximity sensor output isfor a middle distance proximity P2 range, the decrease in the powerlevel of the ALS output from blocking of the ALS sensor by the objectmay be used to (automatically in some cases) alter the control of theproximity sensor output on the proximity determination to cause thedetermination to be changed to a very close distance or touchingproximity P1 range (e.g., more representative of the actual proximity).It can be appreciated that this process allows for conservation orreduction of use of power or battery energy consumed by the device byturning off a display backlight or changing other device settings.

The change in the output levels can be a rate of change and/or an amountof change that is greater than or less than a threshold. A rate ofchange may be described as the rate of increase or decrease of the powerlevel over time. In some cases, the change over time may be described bya mathematical derivative with respect time such as d(power)/d(time) fora selected period of time, or a slope of the power signal as charted ona graph over time. For example, the change may be a rapid (e.g., over ashort period of time) or drastic (e.g., over a wide range of levels)change in the visible light or IR light as determined by one or moresensors, as described herein. Moreover, each sensor output may becompared to a rate of change or amount of change threshold to alter aneffect of a proximity sensor output on control of a proximitydetermination. Thus, the ALS sensor output may be received by a portabledevice, processor, or software application as described herein whichalters an effect of a proximity sensor output on control of a proximitydetermination in response to the ALS output signal level exceeding(e.g., by becoming greater than or less than) the threshold.

FIG. 10A is a graph showing an example of a proximity sensor outputversus time. FIG. 10A shows signal 202 with respect to power P versustime T. Signal 202 may be an output of a proximity sensor such as apower level of a signal based on or proportional too a level of IR lightreceived by the proximity sensor from emitted IR light reflected by anormally or highly IR reflective object (e.g., a person's skin, neck orface). For instance, the proximity sensor may emit IR light using anemitter, a portion of the emitted IR light may be reflected by an object(e.g., see object 128, 888 and/or 988) and a portion of the lightreflected by the object may be received by the proximity sensor whichoutputs power level signal 202 based on the received IR light. Power Pmay represent a signal power level or intensity output by the sensor,such as in Watts. Thus, signal 202 may represent a range of powerbetween zero and Pmax (a maximum reflected IR light power for the objectand closest possible actual proximity). The use of the term “range” mayrepresent a range of values, power, or changes described herein. In somecases, a range may describe the relationship between a minimum andmaximum power level range or rate of change of range and time.

FIG. 10A shows signal 202 increasing in power between time T1, T2, andT3; substantially level or stable between time T3 and T4; and decreasingover time between time T4, T5, and T6. At time T2, signal 202 is greaterthan or exceeds threshold P1. Similarly, at time T5, signal 202 is lessthan or becomes lower than threshold P1. Thus, a proximity determinationmay be made based on whether or not signal 202 is greater than thresholdP1, such as to identify a proximity of an object for which the settingof a device will be altered, such as to turn off a backlight of adisplay or disable processing of inputs received at an input device. Itis also considered that a setting of a device may be altered based onthe rate of change of signal 202. For example, the rate of change ofsignal 202 over time between time T1 and T3 may exceed a threshold thuscausing a setting of a device to be altered due to the increase in powerlevel over time. Similarly, a setting of a device may be altered due tothe decrease in power P over time between time T4 and T6. However, asnoted above, depending on the IR light reflectiveness of the objectreflecting the emitted IR light, power P may be attenuated or representless light reflected by the object than for a more reflective object.

FIG. 10B is a graph showing examples of a proximity sensor output and alight sensor output versus time. FIG. 10B shows signal 206, with respectto power P versus time T. FIG. 10B shows signal 206 increasing in powerbetween time T7, T8, and T9; substantially level or stable between timeT9 and T10; and decreasing over time between time T10, T11, and T12.Signal 206 may be similar to signal 202 except that signal 206 is anoutput of a proximity sensor for a less IR reflective object than thatfor signal 202. For instance, signal 206 may be for a low or less thannormally IR reflective object (e.g., a person's dark or grey hair).Thus, although the object reflecting the IR light for signal 202 and 206may have the same proximity or be the same distance from the proximitysensor, signal 206 has a power level and rate of change attenuated orless than that for signal 202. For instance, signal 206 is not greaterthan, does not reach, or does not exceed threshold P1. However, signal206 is greater than or exceeds threshold P2 between time T8 and timeT11. Thus, a proximity determination may be made where signal 206 isgreater than threshold P2, such as to determine a proximity of an objectthat is further away or not as approximate as an object which provides aproximity sensor output that exceeds threshold P1. Similarly, the rateof change of signal 206 between time T7 and T9 may exceed a thresholdsuch as described above for signal 202 and time T1 and T3, but where thethreshold for signal 206 is a lower change with respect to time. Asimilar concept applies for signal 206 and a rate of change between timeT10 and T12, as compared to signal 202. Thus, signal 206 may bedescribed as exceeding a power level or rate of change threshold betweentime T7 and T9, and between time T10 and T12, but not exceedingthreshold P1 or a rate of change such as shown for signal 202 betweentime T1 and T3 and between time T4 and T6.

According to embodiments, when signal 206 exceeds a threshold betweentime T7 and T9 (or between time T10 and T12) but does not exceed anotherthreshold (e.g., threshold P1 or a rate of change described for signal202) the output of an ALS may be consulted, considered, or used to basea proximity determination. For instance, FIG. 10B shows signal 204, suchas an output of an ALS received by a proximity sensor, device,microprocessor, or software application. Signal 204 is shown as powerALS with respect to time T. Power ALS may be described as a power levelof a signal output by an ambient light sensor. For example, descriptionsabove with respect to power P may apply to power ALS, except where powerALS refers to output of an ambient light sensor responsive, based on, orproportional to ambient light incident upon the ambient light sensor,instead of IR light reflected by an object incident upon a proximitysensor. Signal 204 is shown decreasing between time T7 and T9, stable,level or at a minimum between time T9 and T10, and increasing betweentime T10 and T12. Signal 204 is less than or falls below threshold P3between time T8 and time T11. Otherwise, signal 204 is greater than orabove threshold P3.

Signal 204 may represent an ALS output for a sensor adjacent to,approximate to, or next to the sensor for which signal 206 is aproximity output. Thus, it can be appreciated that the changes,exceeding, being greater than, being less than threshold values (e.g.,such as power level or rate of change threshold values) of signal 204and signal 206 may occur simultaneously, contemporaneously, or havingportions that overlap.

For example, signal 202 may represent a case where a proximity sensoradjacent to an earpiece of a portable device is held next to an objecthaving a higher level of IR light reflectiveness. Thus, when signal 202exceeds threshold P1 or a rate of change threshold, a setting of thedevice may be altered. However, signal 206 may be an output of aproximity sensor adjacent to an earpiece of a portable device sensingproximity of an object that has a low IR light reflectiveness or that isless reflective than the object for signal 202. Thus, although signal206 exceeds threshold P2 for a rate of change threshold, it does notexceed threshold P1 or another rate of change. Hence, a proximitydetermination may be altered (automatically in some cases) based onsignal 204, to change the proximity determination from that indicated bysignal 206 to that indicated by signal 202 (e.g., that an object is in aproximity or distance range for a proximity sensor output that exceedsthreshold P1 or a rate of change as described above for signal 202).

FIG. 10C is a flow chart of a method that includes turning off abacklight, disabling processing of inputs, or taking another actionbased on proximity and light sensor outputs in accordance withembodiments of the present invention. FIG. 10C shows process 220, suchas a process that may consider signals 206, 202 and 204. For example, atdecision block 222 it is determined whether or not proximity haschanged, such as based on signal 202 or 206. Block 222 may includedetermining signal 206 has exceeded threshold P2 or a rate of changethreshold between time T7 and T9. If the proximity has not changed,processing returns to block 222. Alternatively, if the proximity haschanged, processing continues to block 224.

At decision block 224 it is determined whether or not proximity haschanged enough. For example, block 224 may include determining whetheror not the proximity (e.g., signal 202 or 206) has exceeded threshold P1or a rate of change described for signal 202 between time T1 and timeT3. If the proximity has changed enough, processing continues to block228. At block 228 a backlight is turned off, processing of an inputdevice is disabled, or another action is taken.

Alternatively, if at block 224 proximity has not changed enough,processing continues to block 226. At decision block 226, it isdetermined whether or not light has changed enough. Block 226 mayinclude determining whether signal 204 is less than threshold P3 or hasa rate of change that is less than a threshold between time T7 and timeT9. If at block 226 the light has not changed enough, processing returnsto block 222. Alternatively, if at block 226 the light has changedenough, processing continues to block 228.

Thus, process 220 may be described as making a proximity determinationthat an object is not within a certain or selected proximity if theproximity sensor output does not exceed a first and second threshold, orif the proximity sensor output does not exceed a certain threshold andthe ALS sensor does not exceed a certain threshold. Alternatively, itmay describe making a proximity determination that an object is notwithin the selected proximity if the proximity sensor output exceeds afirst threshold but the ALS sensor output does not exceed a threshold.

In another example, FIG. 10D is a flowchart of a method that includesaltering an effect of a proximity sensor output on a proximitydetermination based on a proximity sensor output and an ambient lightsensor output. FIG. 10D shows process 230, such as a process that mayconsider signals 206, 202 and 204. For example, at decision block 232 itis determined whether or not a proximity sensor output, such as based onsignal 202 or 206, is greater than (e.g., exceeds) threshold A (e.g., athreshold indicating that a user actions, such as putting the deviceclose to the user's head). Block 232 may include determining if aproximity sensor output power level or rate of change has exceededthreshold A. If the output has not exceeded threshold A, processingreturns to block 232. Alternatively, if the output has exceededthreshold A, processing continues to block 234.

At decision block 234 it is determined whether or not a proximity sensoroutput (e.g., signal 202 or 206) is greater than threshold B (e.g., athreshold indicating that a user actions, such as putting the device upto or against the user's head or ear). For example, block 234 mayinclude determining whether or not the proximity sensor output powerlevel or rate of change has exceeded threshold B. If the proximitysensor output has exceeded threshold B, processing continues to block238. At block 238 an effect of the proximity sensor output on control ofa proximity determination is automatically altered (e.g., to change aproximity determination to an “actual proximity” determination). Thedetermination may be altered automatically, such as by a device, aprocessor, and/or software.

In alternate embodiments, at block 238 an effect of the proximity sensoroutput on control of a proximity determination is non-automaticallyaltered, such as by receiving a user selection to cause the alteration.For instance, upon determining that an alteration is to be made, thedevice, processor, and/or software may prompt the user to confirm orselect the alteration. Upon receipt of the user confirmation orselection, the alteration occurs (e.g., it is optional until userselection).

Alternatively, if at block 234 the proximity sensor output has notexceeded threshold B, processing continues to block 236. At decisionblock 236, it is determined whether or not an ALS output, such as signal204, is less than (e.g., below) threshold C. Block 236 may includedetermining whether an ALS sensor output power level or rate of changeis below threshold C. If at block 236 the output is not low enough,processing returns to block 232. Alternatively, if at block 226 theoutput is low enough, processing continues to block 238.

Thus, process 220 may be described as (automatically in some cases)altering, setting or making a proximity determination of whether anobject is not within a certain or selected proximity distance based onan ALS output.

Also, it is considered that all or a portion of the ALS output based onlight (e.g., back light) emitted by a display of the device andreflected by the object into the ALS. In this case, the portion of lightmay be described as a “pedestal” and be subtracted (e.g., by processinglogic, a processor, or software) from the ALS output prior to basing thealtering of the proximity detection on the ALS output. It can beappreciated that in this case, the pedestal portion of the power outputmay increase simultaneously with increase in power level of theproximity sensor output, and with the decrease in the power level of theALS output from blocking of the ALS sensor by the object.

According to embodiments, a proximity sensor (e.g., of a portabledevice) and/or a portable device may be “operated” by receiving anambient light sensor (ALS) output (level); and altering, (automaticallyin some cases) based on the ALS output, an effect of a proximity sensoroutput on control of a proximity determination. For example, it can beappreciated that at least certain embodiments of the sensors describedherein may output proximity and ALS data (e.g., output signals based onor proportional to received light levels) to a processor or software ofan electronic device, a display device, a data processing device, or adata processing system. This may include sending proximity sensor outputdata (e.g., to detect a proximity of an object) and ALS output level orvalue data (e.g., to determine or identify an ambient light environmentor level of visible light intensity) to a software application (e.g.,instructions executing on a processor). Reference to a “device”, an“electronic device”, a “portable device”, “a data processing system”, a“date processing device” or a “system” herein may describe a portabledevice (such as a lap-top computer or device described for FIGS. 2-11),non-portable device (such as a desktop computer), or a processor orsoftware application (e.g., instructions executed by a processor) of thedevice referred to. Thus, the software or processor can determine, basedupon the data, whether to modify a setting of the device or dataprocessing system. For instance, the processor, software or processinglogic may compare the output data from a proximity sensor to a thresholdvalue and/or compare the output data from one or more ALS to a thresholdvalue to make a proximity determination (e.g., is an object within aproximity distance threshold or range). Specifically, the comparison maybe used to determine when and by how much to modify (e.g., by adjusting,increasing, decreasing, turning on, turning off, or leaving status quo)at least one setting or display control parameter of a displayilluminator or device (e.g., a backlight or input device) as describedherein. For instance, the following descriptions, apply to proximitysensors and portable devices described herein.

Moreover, according to embodiments, a sensor output may represent thevalue or intensity for a plurality of ALS sensors. For example, thedevice, processor, or software application may receive a number ofambient light sensor output levels from a number of sensors. Themultiple sensor outputs may be added together to represent a totalambient light falling on a location of the device. That total ambientlight of the one or more sensors may be normalized to come up with anumber from 0 to 1, with 1 representing full sunlight and 0 representingtotal darkness (e.g., and a lighted room between 1 and 0, with abrightly lit room above a softly or darkly lit room).

Ambient light level data may be provided by an ambient light sensor,which indicates the level of light intensity surrounding that sensor.Ambient light data may also be obtained from two or more ambient lightsensors, which are disposed at different positions on, at, or adjacentto an earpiece of the device. Thus, an ALS sensor at or adjacent to anearpiece may best represent light falling directly on the earpiece. Forexample, see sensors 44, 62, 84 and 92 of FIGS. 2-5A respectively.

Also, according to embodiments, the output of the light sensor may be avalue or level of ambient light (e.g., visible ambient light) sent bythe sensor and received by a device, processor, or software application.For example, the light sensor “value” may be an ALS level, or output,such as a reading, electrical signal level or amplitude output by an ALSbased on a level or intensity of ambient light received by or incidentupon the ALS.

In some cases, the ALS level or output is a change in ALS level and thechange causes the proximity determination to change.

In some embodiments, based on a received output and/or data acquiredfrom one or more sensors, a digital processing system (e.g., a portabledevice) may (automatically in some cases) alter or change a setting ofthe system, such as according to an algorithm implemented by a softwareapplication. For instance, a system or device may have various device orfeature settings, such as a display, display backlight, and user inputprocessor or processing. These setting may includes those of a digitalprocessing system, such as, for example, activating, deactivating,changing, controlling, and/or altering a setting (e.g., a parameter) ofa backlight. Other responses that may be performed include changing asetting of, or disabling processing of inputs received at an inputdevice. For example, altering a setting may include turning off thebacklight of the portable device's display, suppressing the user'sability to input at the user interface (e.g., locking the input device),changing the telephone's mode, and the like. It will be appreciated thatcombinations of the above actions may also be implemented by the device,proximity sensor, processor, and/or software of the device, such as toboth turn off a display's backlight and suppress the user's ability toinput at a user interface.

Also, in some embodiments, the ALS sensor output may be used inconnection with other sensor outputs, such as an accelerometer output, ablob sensor output, an irregular contacts output, a capacitive sensoroutput, a far-field recognition sensor output, and the like.Specifically, according to some embodiments, in addition to using an ALSoutput to more accurately determine “actual proximity”, an accelerometeroutput, a blob sensor output, an irregular contacts output, a capacitivesensor output, a far field recognition sensor output power level orchange in power level received from one or more of such sensors may beused, consulted, or a basis to operate a proximity sensor of a portabledevice by (automatically in some cases) setting, altering or changing aproximity determination.

In some cases, the effect of the proximity sensor output on theproximity determination may be altered, (automatically in some cases)based on an accelerometer output, such as where the output indicatesthat the device has accelerated, decelerated, or accelerated and thendecelerated by an amount greater than a threshold amount. Theaccelerometer output may include or indicate strong movement recorded byan accelerometer, such as an accelerometer as known in the art.

Also, in some cases, the effect of the proximity sensor output on theproximity determination may be altered, (automatically in some cases)based on a blob detect output. The blob detect output may also bedescribed as a “irregular contacts” output that detects irregularcontacts that are larger than a fingertip (e.g. a whole ear, a face, ahead, or a palm of a user). The “blob” may be contacts that haveirregular (non-ellipsoid) shape or rough, ragged texture/topology. Insome cases, the blob detect output may indicate or determine that thedevice is held in a hand and/or up to (e.g., touching, against, adjacentto, or hovering above) a face or head of a user. The determination maybe altered based on the capacitive detection inputs of a number ofsimultaneous capacitive input detections to a plurality of input keys orlocations of an input device, such as in an irregular location patternor shape of the input detections. The blob detect sensor or irregularcontacts sensor may include an input device (e.g., a multi-point touchscreen), and associated processing logic and/or software. Additionalinformation about such blob detect sensor or irregular contacts sensorsand outputs can be found in U.S. patent application Ser. No. 11/619,464,filed Jan. 3, 2007 by Wayne C. Westerman, titled “Multi-Touch InputDiscrimination”; and U.S. patent application Ser. No. 11/619,490, filedJan. 3, 2007 by Wayne C. Westerman, titled “Irregular InputIdentification”, which are both incorporated herein by reference intheir entireties.

Moreover, in some cases, the effect of the proximity sensor output onthe proximity determination may be altered, (automatically in somecases) based on a far-field recognition output. The far-fieldrecognition output may be an output to detect large objects (e.g. aface, a head, or a palm of a user) near the multitouch sensors via patchradii thresholding or farfield measurement techniques. In some cases,the far-field recognition output may indicate or determine that thedevice is held in a hand and/or up to (e.g., hovering above) a face orhead of a user. The far-field recognition sensor may include an inputdevice (e.g., a multi-point touch screen), and associated processinglogic and/or software. Additional information about such far-fieldrecognition sensors and outputs can be found in U.S. patent applicationSer. No. 11/619,505, filed Jan. 3, 2007 by Wayne C. Westerman and SteveHotelling, titled “Far-Field Input Identification” which is incorporatedherein by reference in its entirety.

It can also be appreciated that the concepts described above foraltering a proximity determination based on ALS output decrease in powerlevel or rate of decrease of power level also apply to altering aproximity determination based on increase in power level or rate ofincrease of power level. For instance, when a power level or rate ofchange of power level of an ALS increases, such as to identify moreambient light incident upon the ALS, a backlight or input processing maybe turned on or activated. The increase in power or change may indicatethat the device is no longer held to the ear of the person.

FIG. 11 shows another example of a device according to an embodiment ofthe inventions. This device may include a processor, such asmicroprocessor 402, and a memory 404 (e.g., a storage device), which arecoupled to each other through a bus 406. The device 400 may optionallyinclude a cache 408 which is coupled to the microprocessor 402. Thisdevice may also optionally include a display controller and displaydevice 410 which is coupled to the other components through the bus 406.One or more input/output controllers 412 are also coupled to the bus 406to provide an interface for input/output devices 414 (e.g., userinterface controls or input devices) and to provide an interface for oneor more sensors 416 which are for sensing user activity. The bus 406 mayinclude one or more buses connected to each other through variousbridges, controllers, and/or adapters as is well known in the art. Theinput/output devices 414 may include a keypad or keyboard or a cursorcontrol device such as a touch input panel. Furthermore, theinput/output devices 414 may include a network interface which is eitherfor a wired network or a wireless network (e.g. an RF transceiver). Thesensors 416 may be any one of the sensors described herein including,for example, a proximity sensor or an ambient light sensor. In at leastcertain implementations of the device 400, the microprocessor 402 mayreceive data from one or more sensors 416 and may perform the analysisof that data in the manner described herein. For example, the data maybe analyzed through an artificial intelligence process or in the otherways described herein. As a result of that analysis, the microprocessor402 may then (automatically in some cases) cause an adjustment in one ormore settings of the device.

Next, “control” of a proximity determination may describe augmentingsetting, changing, effecting, determining, altering, or adjusting theproximity determination, proximity location, or proximity distance of anobject to a proximity sensor. In some cases, controlling may describeaugmenting a proximity sensor output using and ALS output to make a moreaccurate proximity determination.

Moreover, use of the term “effect” herein may describe changing a value,scalar or range determination of a proximity stored in a memory, logic,processing logic, register, or software, such as by multiplying,increasing, or pushing to the next value or range, the output signal orvalue of a proximity sensor. In some cases, “effect” may describe usingsoftware to apply a “gain” to an output of a sensor or photodiode.

Also, the term “automatically” may describe a cause and effectrelationship, such as where something is altered, changed, or setwithout receiving a user input or action directed at the altered orchanged result. For example, a received ALS output used for determiningsomething other than for proximity determination, may also cause anadditional change in a proximity determination (e.g., automatically) inaddition to causing a determination of the other thing. In some cases,“automatically” may describe a result or determination that is asecondary result or in addition to a primary result or determinationaccording to an ALS output. For instance, an output power level orchange in power over time received from an ALS may not only cause achange in an ALS determination or reading (e.g., according to ALS outputthresholds or criteria for the output), but may also cause an additionalchange in a proximity determination by altering (e.g., automatically)the effect of a proximity sensor output on the proximity determination.

According to some embodiments, the concepts described above (e.g., forFIGS. 1-11) may be implemented using a machine accessible mediumcontaining instructions (e.g., such as storage device 104, memory 404,or executable program/software instructions stored thereon) that, whenexecuted, cause a machine or processor (e.g., such as digital processingsystem 103, microprocessor 153, or processor 402) to perform (e.g.,automatically or not) one or more actions. The actions may include thereceiving, altering, controlling, generating, displaying, relating,processing, processes, and/or other actions, described herein, such asto operate a data processing system, portable device, electronic device,proximity sensor, display, display control parameter, backlight controlparameter, input device, or user input as described herein.

Finally, it can be appreciated that the proximity sensor output (e.g.,signal level or value), proximity determination, display setting, lightsensor output (e.g., ALS output signal level or value), and/or devicesetting described herein may be stored in a machine accessible medium,such as a memory or data storage device (e.g., device 104, memory 404,system 103, processor 153, processor 402, and the like). In some cases,the stored values, selections, or levels, etc. noted above may beaccessed by a device or processor to determine or calculate an actualproximity of an object to a proximity sensor, portable device, and/orearpiece.

In the foregoing specification, the invention has been described withreference to specific exemplary embodiments thereof. It will be evidentthat various modifications may be made thereto without departing fromthe broader spirit and scope of the invention as set forth in thefollowing claims. The specification and drawings are, accordingly, to beregarded in an illustrative sense rather than a restrictive sense.

1. A method of sensing proximity, the method comprising: receiving a first intensity level output from a proximity sensor; determining an estimated distance value between the proximity sensor and a surface of an object based on the received first intensity level output from the proximity sensor; receiving a second intensity level output from an ambient light sensor (ALS); determining, based on the second intensity level output from the ambient light sensor that the estimated distance value between the proximity sensor and the surface of the object is incorrect; changing, by a data processing system, the estimated distance value using the second intensity level output from the ambient light sensor.
 2. The method of claim 1, wherein the second intensity level output corresponds to a visible light level of ambient light received by an ALS sensor adjacent to a proximity sensor that provides the first intensity level output, and the ALS sensor and the proximity sensor are located adjacent to an earpiece of a portable device.
 3. The method of claim 1, wherein changing the estimated distance value comprises changing the proximity of the object from a proximity greater than a first threshold to a proximity less than the first threshold.
 4. The method of claim 3, wherein the first intensity level output is one of a power level and a rate of change of a power level of emitted IR light reflected by the surface of the object and received by the proximity sensor, and the second intensity level output is one of a power level and a rate of change of ambient light received by the ALS.
 5. The method of claim 4, wherein the second intensity level output is a change in ALS intensity level and the change causes the estimated distance value change.
 6. The method of claim 4, wherein the rate of change of second intensity level output exceeding the threshold occurs simultaneously with the rate of change of first intensity level output.
 7. The method of claim 1, further comprising one of: turning off a backlight of a display, automatically, based on the estimated distance value change, and disabling processing of inputs received at an input device, automatically based on the first intensity level output.
 8. The method of claim 1, wherein the first intensity level output is a power level that exceeds a first threshold but does not exceed a second threshold, the second threshold determining a proximity of an object, wherein the second intensity level output is a rate of decrease of ambient light less than a third threshold.
 9. The method of claim 8, wherein the first intensity level output of the proximity sensor output occurs simultaneously with the rate of change of the second intensity level output.
 10. The method of claim 9 wherein a portion of the second intensity level output is light emitted by a display and reflected by the object into the ALS, and the portion is a value subtracted from the second intensity level output prior to basing the changing on the second intensity level output.
 11. The method of claim 1, further comprising: receiving an accelerometer output; and wherein changing further comprises changing, automatically based on the accelerometer output, the effect of the first intensity level output on the estimated distance value.
 12. The method of claim 11, wherein the accelerometer output comprises strong movement recorded by an accelerometer.
 13. The method of claim 1, further comprising: receiving a blob detect output; and wherein changing further comprises changing, automatically based on the blob detect output, the effect of the first intensity level output on the estimated distance value.
 14. The method of claim 13, wherein receiving blob detection output further comprises: receiving a plurality of simultaneous capacitive input detections to a plurality of input locations of an input device; and wherein changing further comprises changing, automatically based on the capacitive detection inputs, the effect of the first intensity level output on the estimated distance value.
 15. The method of claim 14, wherein the blob detection comprises an irregular location pattern or shape of the plurality of input detections.
 16. The method of claim 1, further comprising: receiving a far-field recognition output; and wherein changing further comprises changing, automatically based on the far-field recognition output, the effect of the first intensity level output on the estimated distance value.
 17. The method of claim 1, further comprising changing a setting of one of a display of the portable device and an input device of the portable device, automatically based on the estimated distance value change.
 18. The method of claim 17, wherein changing a setting further comprises one of: turning off a backlight of a display and disabling processing of inputs received at an input device.
 19. The method of claim 1, wherein the object is a low IR reflective object at a greater proximity than the estimated distance of the object, the second intensity level output is based on an actual proximity of the object to the ALS, and changing comprises changing the estimated distance value to be the actual proximity of the object.
 20. The method of claim 19, wherein generating comprises generating a plurality of estimated distances that decrease over a period of time; wherein the object is moving towards the proximity sensor over the period of time; wherein receiving comprises receiving a plurality of second intensity level outputs that decrease over the period of time; and wherein the actual proximity of the object is closer than the corresponding estimated distance over the period of time.
 21. The method of claim 19, further comprising: generating a second estimated distance from a second first intensity level output of the proximity sensor detection of a second, high IR reflective object; receiving a second intensity level output based on a second actual proximity of the second object to the ALS, wherein the second actual proximity is the same as the second estimated distance; not changing, in response to the second intensity level output, the second estimated distance.
 22. A non-transitory machine readable medium containing executable program instructions which when executed cause a method of operating a data processing system, the method comprising: receiving a first intensity level output from a proximity sensor; determining an estimated distance value between the proximity sensor and a surface of an object based on the received first intensity level output from the proximity sensor; receiving a second intensity level output from an ambient light sensor; determining, based on the second intensity level output from the ambient light sensor that the estimated distance value between the proximity sensor and the surface of the object is incorrect; changing, by a data processing system, the estimated distance value using the second intensity level output from the ambient light sensor.
 23. A portable data processing device comprising: a means for receiving a first intensity level output from a proximity sensor; a means for determining an estimated distance value between the proximity sensor and a surface of an object based on the received first intensity level output from the proximity sensor; a means for receiving a second intensity level output from an ambient light sensor; a means for determining, based on the second intensity level output from the ambient light sensor that the estimated distance value between the proximity sensor and the surface of the object is incorrect; a means for changing, by a data processing system, the estimated distance value using the second intensity level output from the ambient light sensor.
 24. A portable data processing device comprising: hardware logic for: receiving a first intensity level output from a proximity sensor; determining an estimated distance value between the proximity sensor and a surface of an object based on the received first intensity level output from the proximity sensor; receiving a second intensity level output from an ambient light sensor; determining, based on the second intensity level output from the ambient light sensor that the estimated distance value between the proximity sensor and the surface of the object is incorrect; changing, by a data processing system, the estimated distance value using the second intensity level output from the ambient light sensor. 